<html>
    <head>
        <meta name="viewport" content="width=device-width, initial-scale=1" />
    </head>
    <body>
        <div>
            <img width="100%" src="/update" id="img"></img>
        </div>
    </body>
    <script>
        let acc=0;
        setInterval(()=>{
            acc++;
            document.querySelector('#img').src="/update?interval="+acc;
        }, 15 * 1000)
    </script>
</html>